Microplastics are small pieces of plastic that cannot be seen with the naked eye. The pieces are less than 5 mm in length, and can even break down into smaller nanoplastics (<1 µm) that are a thousand times smaller than an algae cell. In the last decades, the concentrations of microplastics in the oceans have drastically increased, raising many concerns for the environment, as well as human health. Even though it seems trivial that microplastics in our environment cannot be any good, much is still unknown about the dangers of microplastics.

There are different types of microplastics; they can either be primary or secondary. Primary microplastics are intentionally manufactured to this size, and can e.g. be found in cosmetics in the shape of microbeads for exfoliating purposes. Secondary microplastics are the result of plastic fragmentation: a combination of UV light, biodegradation, and mechanical action (such as wave moment) cause bigger plastics such as bags and bottles to break down into smaller parts.

Microplastics have been spread pretty much everywhere across the globe – from the soil, our oceans, and waterways, to fish and other animals, as well as table salt, drinking water, and beer, and microplastics have even been found in human brains. Even though most research has focused on microplastics in our oceans, they have been found in soils and also have traveled across continents by floating through the air.

It’s also been shown that microplastics can travel through the food web, which could mean that it accumulates at the top of the food chain – which is where we humans are too, amongst other predators such as seals.

It’s been estimated that there are around 12.5 – 125 trillion plastic particles floating around in the oceans globally, a number that varies a lot depending on what type of nets are used to catch the particles. Much still remains uncovered about the seafloor, as most research is based on plastic on the sea surface. In fact, in a deep-sea trench just off the coast of Italy, researchers found a thin layer of 1.9 million microplastics in just one single square meter!

A study from 2020 estimated that humans breathe in 1,900 to 100,000 microplastic particles from indoor air only. Considering that plastic production has increased from an annual 1.7 million to 288 million tons, the number of microplastics in the oceans, soil, and the air is bound to increase drastically unless we do something about it.

The consequences of microplastics for wild animals, marine and terrestrial ecosystems, as well as human health, are still largely unknown. One of the reasons why it’s complicated to estimate the dangers of microplastics is that two of these particles are never the same: they can differ in size, shape, colour, and type of plastic, and there is no standardized way of quantifying them nor estimating its consequences. It’s also tricky to understand how laboratory exposure to microplastics reflects what exposure to microplastics looks like in daily life.

Microplastics are potentially dangerous because of multiple reasons. First of all, the ingestion of foreign material could be harmful, especially if these materials build up within organs and travel across the food chain – organisms at the top of the food chain (like us) will therefore have to deal with an accumulation of microplastics. Secondly, microplastics contain additives and contaminants, such as bisphenol A (BPA), phthalates, polybrominated diphenyl ethers (PBDE), nonylphenol, and triclosan that are toxic. Lastly, microplastics attract other chemical contaminants from their surroundings which then stick to their surfaces, meaning they can become a vector of multiple contaminants and become more dangerous over time.

So far, experiments, as well as mathematical models, have helped us figure out the following, among others:

• Studies have revealed that microplastics threaten marine organisms, by changing their reproduction, decreasing growth, causing organ damage and inflammation, and changing cognition and behaviour. For example, it has been found that fish that feed on phytoplankton cannot distinguish between microplastics and food when the plastics are four times smaller than the food particles and digesting these microplastics worsened the fish’s body condition. Another study found that exposing hermit crabs to microplastics appeared to impair their ability to select optimal shells for them to live in, which is essential for their survival.
• Microplastics are also found in soils, which can disturb plant productivity as the soil might get drier, water cannot move as well through the soil, and the toxic particles impair plant growth. The microplastics in the soil can also end up in our produce, which is consequently eaten by us or by livestock, and again make its way up the food chain.
• In humans, it’s been found that microplastics can cause skin irritation, respiration problems, the potential for cancer, cardiovascular diseases, and reproductive problems. A variety of chronic diseases have bene liked to microplastics. One of the best-known ways in which microplastics can be ingested is through eating seafood, but they can also build up inside our bodies through inhalation of city dust and synthetic textiles, drinking water or eating salt, and through skin contact (sweat glands, wounds, hair follicles). The particles can travel through our body and end up, for example, in the placenta or even cross the blood-brain barrier. The scientists that detected microplastics in the blood-brain barrier found that the particles build up in parts of the brain that are crucial for maintaining the nervous system and that this causes the cells to die off, which alters our immune responses and inflammatory responses.

Scientists predict that even though the current levels of microplastics might not be majorly detrimental yet to ecosystems and human health, they are likely to in the near future. The levels of microplastic particles have been estimated to increase from 188 to 380 million tonnes, even when carefully disposed of in landfills. We, therefore, have to avoid this increase to evade non-reversible consequences, by limiting and reducing microplastic pollution.

1. The single most important thing to avoid plastic waste is to stop producing more plastic and specifically, stop single-use plastics:

“There’s no point producing things that last for 500 years and then using them for 20 minutes”.

Even if all plastic production is stopped, the oceans will keep being polluted by plastic by all the plastic that is already swimming in the oceans.

2. Secondly, don’t buy cosmetics that contain primary microplastics. Sometimes, the “microplastic-free” label helps identify such products, but there are some types of microplastics that can still be added despite this label. Follow these guidelines to avoid them:

• Don’t buy any products that contain more than 20 ingredients. The more ingredients, the more unnecessary things are added to reduce production costs, such as microplastics.
• Only buy 100% natural products – sometimes products are ±95% natural but can still contain plastics in the remaining 5%.
• Avoid ingredients that contain the words poly-(mer), or acronyms such as PVA and PEG.

3. Other than cosmetics, washing your clothes can lead to the release of microplastics that come from the synthetic fibers your clothes are made from, such as nylon, fleece, polyester, and spandex. By washing less often and buying clothes that are not made from synthetics, but rather natural materials (linen, cotton, silk, wool, alpaca, and Tencel), you will avoid microplastics shedding into wastewater. Another option would be to filter out the microplastics from your laundry. Check out our catalog for some companies that sell these filters!

4. Another major player in microplastic pollution is tea and its plastic packaging. Companies can use polypropylene to seal off the teabags, which has been found to release up to 3.1 billion microplastics in a single cup of tea! By choosing teabags that are sealed without using plastic, or even better; loose-leaf tea, you avoid this microplastic shedding and ingestion.

5. The last, maybe the most obvious, visible way for microplastics to be released into the environment is through glitter. Glitter can be found in cosmetics, clothes, bags, toys, bath bombs, and shoes. Because they are used for multiple causes, glitters can contaminate almost any place as they easily spill and enter our sewage systems. They are therefore expected to be more dangerous for the environment than microbeads are. Using biodegradable glitter, or avoiding them to start with is therefore crucial to avoid this stream of pollutants.